What is the average duration in the hospital if for someone with an aaa?

Depends on Approach. Elective AAA surgery can be done "open" or via "endovascular" means. If the anatomy of the aneurysm is amenable to an endovascular approach, patients typically go home the day after surgery with groin incisions. If an open aneurysm repair is required, the hospital stay is typically between 4 and 10 days. If either of the above is done in an emergency / AAA rupture setting, the stays are longer.
Duration AAA. With open AAA usually 6-8 days. With endovascular AAA an overnight stay is usual.
Depends. Open AAA repair in otherwise healthy young patient will require around one week in the hospital but for endovascular repair the stay is typically 24 hours.